Update transforms module to PEP 585 type hints

[jrmccluskey]

Updates the transforms module to PEP-585 type hint standards. Does not update the enrichment handlers, that will be a later PR.

Part of #32969

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[tvalentyn]

looks like there are some conflicts, overall LGTM if tests pass.

[github-actions]

Reminder, please take a look at this pr: @tvalentyn